In a recent publication, analytical method validation of three different PD biomarker assays was reported: quantitative RT–PCR (qRT–PCR) for XIAP mRNA expression, Western blot analysis for XIAP protein expression, and a novel plasma Elisa assay (M30 Apoptosense) as a surrogate marker of tumour cell apoptosis (Cummings et al, 2005). This evidence concerns the gene XIAP and neoplasm.